During the recent cold snap, our clients who are now living in their Porters house have been amazed by the house's incredible performance, with very little heat required to warm the large 297m2 house. In fact during even the coldest days a 4 hour run on the small lounge log stove (with back boiler) charges the thermal store sufficiently for the MVHR heater battery to provide all the heating to the large home for a 24 hour period, along with all the hot water requirements of the home. And on the odd winter day when the sun did shine, this allowed the large solar array to charge the thermal store sufficiently for a days worth of heat and hot water.
With rising oil and gas prices and huge concern over climate change, building a house to the passivhaus specification provides a 90% saving on heating demand (and so cost), with the heat required provided by locally sourced logs - much more reliable then foreign oil!
